Dixie is correct about it taking more than just a regular bullet to ignite the tanks. I believe the US models (and others, too, I’m sure) used an electric ignition system - but older flamethrowers required a burning “wick” to ignite the fuel as it left the weapon. I suppose if spray from leaking tanks hit that… And the danger was not limited to damage to the tank. Men armed with flamethrowers were rarely taken prisoner: on-the-spot execution was the preferred means of dealing with them, because nobody wanted to be on the weapon’s receiving end. The German army often assigned soldiers to the flamethrower as a punishment…